大气中短链/中链化的发生和命运:大小分布和吸入暴露
Naibing Liang1, Rong Cao2, Nan Jiang3
1Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; College of Ecology and Environment, Zhengzhou University, Zhengzhou 450001, China.
The Science of the total environment
|September 28, 2024
概括
短链和中链化 (CPs) 缩在较小的大气颗粒中. 这些CP主要沉积在上呼吸道,较小的颗粒大小会给健康带来更高的风险.
科学领域:
- 环境化学环境化学
- 毒理学 毒理学 毒理学
- 大气科学 大气科学
背景情况:
- 甲 (CPs) 是工业化学品,对其大气颗粒物 (PM) 分布的研究有限.
- 了解PM中短链 (SCCPs) 和中链化抛 (MCCPs) 的尺寸依赖性行为至关重要.
研究的目的:
- 调查大气中的PM中CP的尺寸分布.
- 分析CP在人体呼吸道中的沉积模式.
- 根据颗粒大小,评估吸入CP的健康风险.
主要方法:
- 分析大气PM的不同尺寸分数中的SCCP和MCCP度.
- 对吸入性CP的呼吸道沉积的建模.
- 基于颗粒大小和沉积的每日摄入值的估计.
主要成果:
- 在PM10中的SCCP度 (2.53-31.8 ng m−3) 比MCCP度 (1.07-4.62 ng m−3) 高.
- 随着颗粒体大小的减少,CP度增加,气动直径 (Dp) <0.49μm的颗粒达到峰值.
- 物理化学性质影响了PM中的CP同质分布;较低的蒸汽压力和较高的分离系数与较大的颗粒积累相关.
- 吸入的CP主要沉积在上呼吸道,较小颗粒大小 (Dp < 0.49 μm) 的估计每日摄入量较高.
结论:
- 颗粒大小是影响呼吸道中CP沉积的关键因素.
- 对于CPs的健康风险评估必须考虑它们与特定的PM大小小部分的关联.
- 需要进一步的研究,才能充分了解CPs在大气PM中的环境命运和毒理影响.
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